一层或一个管? 揭示决定分层协调聚合物的关键因素
Jia-Ge Jia1, Chen-Chen Zhao2, Song-Song Bao1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, People's Republic of China.
Journal of the American Chemical Society
|October 13, 2021
概括
本研究探讨了弱相互作用和水如何影响分层或管状协调聚合物 (CP) 的形成. 研究人员发现,在特定的CP系统中,水是层到管的转变的驱动力.
科学领域:
- 材料科学
- 超分子化学
- 晶体学
背景情况:
- 像碳纳米管这样的纳米管材料被广泛研究.
- 无机纳米管的层到管滚动机制已知,但对协调聚合物 (CP) 的理解较少.
- 研究控制CP结构形成的因素对于设计新材料至关重要.
研究的目的:
- 发现关键因素决定了多层CP的卷积成纳米管.
- 研究弱相互作用和客分子对CP结构的影响.
- 探索水在层到管的转化中的作用.
主要方法:
- 用不同的替代物 (X=H,F,Cl,Br) 合成和描述Co/Xpemp协调聚合物.
- 使用同质素和血细胞前体的结构研究.
- 包括客分子 (3,3'-azobipyridine,ABP) 来影响结构.
- 基于水热和溶剂的实验来研究结构转变.
- 理论计算以合理化实验发现.
主要成果:
- 在某些情况下,Homochiral Co/Xpemp化合物形成了管状结构,而ABP的加入导致了层状结构 (X=Cl,Br).
- 对于raceme的Co/Xpemp化合物,除了X=H外,还观察到分层结构.
- 在水热条件下去除ABP时观察到特定化合物 (R-6Br) 的层到管的转化,这表明了水的作用.
- 在有机溶剂中没有发生这种转化,这凸显了反应介质的重要性.
结论:
- 薄弱的层间相互作用是必要的,但不足以在CP中进行层滚动.
- 在这些协调聚合物系统中,水起着关键的驱动作用.
- 这些发现提供了通过外部刺激和反应条件控制CP的维度的见解.
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